Which Factory action for a semi-custom rifle???

If you were going to build a semi-custom, and what I mean by that is that you are going to use one of these two actions and rebarrel them to a different caliber but one that WILL actually fit either, which would you use and why? Which ACTION do you think would be more accurate from the box, and which do you think is more "stout?"

I needed some parts (sear, sear spring,recoil spring) for a CZ automatic handgun and had no problem getting them from CZ USA in Kansas City. Many Ruger parts are not available outside of the factory, they want you to send the gun to them, and they don't like modifications, although, they have a pretty short turn around time.